Method for improving flavor of lotus root whole powder

Abstract

The invention provides a method for improving the flavor of lotus root whole powder, and relates to the technical field of agricultural product processing. The method for improving the flavor of the whole lotus root flour comprises the following steps: cleaning fresh lotus roots, removing peel and knots, slicing, drying lotus root slices with hot air, spraying lysine on the surfaces of the lotus root slices, baking, and cooling, grinding and sieving after the lotus root slices are dried to obtain the whole lotus root flour. The defects in the prior art are overcome, the hot air drying and baking combined technology is adopted, compared with traditional hot air drying, the processing time is short, and the product has better solubility and dispersity; compared with single baking, the product has better appearance characteristics; and exogenous lysine is added, so that the chemical reaction in the baking process can be better promoted.

Description

Technical Field

[0001] The invention relates to the technical field of agricultural product processing, and in particular to a method for improving the flavor of whole lotus root flour. Background Art

[0002] Lotus root is rich in carbohydrates, polyphenols, amino acids and other nutrients. It is an aquatic vegetable that is deeply loved by consumers. Lotus root powder, also known as lotus root powder, is mainly processed by washing, peeling, drying, crushing, etc. Compared with traditional lotus root starch, lotus root powder has a simple processing technology, low energy consumption, and is green and environmentally friendly. It can fully retain the functional active ingredients of the raw materials, such as dietary fiber and polyphenols. Lotus root powder has similar product forms and eating methods as lotus root starch, and has good application prospects as a substitute for lotus root starch.

[0003] At present, the research and application of lotus root powder mainly focuses on the optimization of formulas for instant products, improvement of nutrition and processing quality, drying and color protection, and application in food. For example, using whole lotus root powder, xylitol, flavor powder and konjac powder as raw materials, research and develop foods with good solubility and low glycemic index (GI); heat treatment (100°C and 120°C steam heating) can change the nutritional characteristics and digestive characteristics of lotus root powder; spray drying technology is used, combined with color protection pretreatment before drying and optimization of drying process parameters, to obtain lotus root powder with bright white color and good taste; Patent CN202311364401.0 introduces a lotus root powder jelly with the function of regulating intestinal inflammation and its preparation method, in which the lotus root powder is ultrafine whole lotus root powder. However, there are few reports on the improvement of flavor substances in lotus root powder during the drying process and lotus root powder with a baked aroma. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention provides a method for improving the flavor of whole lotus root powder. The method combines hot air drying with baking and performs lysine spraying treatment before baking, so as to increase the flavor substances of the whole lotus root powder and enrich the product types of the whole lotus root powder.

[0005] To achieve the above objectives, the technical solution of the present invention is implemented through the following technical solutions:

[0006] A method for improving the flavor of lotus root powder, the method comprising the following steps:

[0007] (1) Raw material cleaning: wash the fresh lotus root, remove the nodes, peel it, and evenly slice it;

[0008] (2) placing the lotus root slices on a clean gauze, and evenly spreading them in an oven for hot air drying to obtain hot air dried lotus root slices;

[0009] (3) spraying the lysine solution evenly on the surface of the dried lotus root slices;

[0010] (4) transferring the lotus root slices sprayed in step (3) into an oven for baking, and obtaining the baked lotus root slices for later use;

[0011] (5) Grinding and sieving the roasted lotus root slices to obtain lotus root whole powder.

[0012] Preferably, the thickness of the slices in step (1) is 3-5 mm.

[0013] Preferably, the hot air drying temperature in step (2) is 60-80° C. and the drying time is 2-4 hours.

[0014] Preferably, the concentration of the lysine solution in step (3) is 0.25-0.35 g / L.

[0015] Preferably, the baking parameters in step (4) are: upper heat 105-115° C., lower heat 120-130° C., and baking for 8-12 minutes.

[0016] The present invention provides a method for improving the flavor of lotus root powder, which has the following advantages compared with the prior art:

[0017] The present invention adopts hot air drying combined with baking technology. Compared with traditional hot air drying, the processing time is short and the product has better solubility and dispersibility; compared with single baking, the product has better appearance characteristics; adding exogenous lysine can further promote chemical reactions in the baking process and increase the formation of flavor substances. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The radar diagram of the electronic nose sensor of different lotus root powders in the present invention;

[0019] Figure 2 The fingerprints of volatile flavor substances of different lotus root whole powders in the present invention are shown. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention is clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] Embodiment 1:

[0022] Preparation of lotus root powder:

[0023] (1) Wash, remove nodes and peel fresh lotus roots, and cut the lotus roots into 4 mm thick slices;

[0024] (2) subjecting the lotus root slices in step (1) to hot air drying at a temperature of 70° C. for a drying time of 3 h;

[0025] (3) spraying the lotus root slices prepared in step (2) evenly with 0.3 g / L lysine solution;

[0026] (4) baking the lotus root slices in step (3) at a temperature of 110° C. for upper heating and 120° C. for lower heating, for 10 min;

[0027] (5) Grind the lotus root slices in step (4) and pass them through an 80-mesh sieve to obtain lotus root whole powder.

[0028] Comparative Example 1:

[0029] Preparation of lotus root powder:

[0030] Wash the fresh lotus root, remove the nodes and peel it, cut the lotus root evenly into 4 mm thick slices, pre-freeze at -20°C for 24 h, and then vacuum freeze-dry (-80°C, 35 Pa) for 48 h, and then grind it through an 80-mesh sieve to obtain lotus root whole powder.

[0031] Comparative Example 2:

[0032] Preparation of lotus root powder:

[0033] (1) Wash, remove nodes and peel fresh lotus roots, and cut the lotus roots into 4 mm thick slices;

[0034] (2) subjecting the lotus root slices in step (1) to hot air drying at a temperature of 70° C. for a drying time of 3 h;

[0035] (3) baking the lotus root slices in step (2) at a temperature of 110° C. for upper heating and 120° C. for lower heating, for 10 min;

[0036] (4) Grind the lotus root slices in step (3) and pass them through an 80-mesh sieve to obtain lotus root whole powder.

[0037] Detection:

[0038] 1. Electronic nose analysis:

[0039] Weigh 3.0±0.1 g of the lotus root powder samples of Example 1 and Comparative Examples 1-2, respectively, and heat them at 60° C. for 30 min in a 50 mL headspace bottle for testing. Test three samples of each sample in parallel using an electronic nose for detection.

[0040] Specific instrument settings: preheating for 30 minutes, sensor cleaning time for 200 seconds, sample test time for 200 seconds, internal flow rate of 300 mL / min, injection flow rate of 300 mL / min. The data that tends to be stable during the measurement process are selected for subsequent analysis. The sensor must be cleaned and standardized before and after each measurement;

[0041] Specific results such as Figure 1 As shown: the response value of comparative example 1 is about 1.2, and the reaction is small. Except for the response values ​​of sensors S3 (hydrogen), S10 (hydrogen), S17 (hydrogen-containing substances) and S25 (sensitive to alkanes, carbon monoxide, olefins, alcohols, nitrogen oxides, ketones, aldehydes, etc.), the other response values ​​of Example 1 are significantly higher than those of comparative examples 1 and 2. This shows that the odor components in the whole lotus root powder prepared by hot air drying combined with baking are significantly more than those prepared by freeze drying, and the addition of lysine before baking significantly increases the volatile components in the whole lotus root powder.

[0042] 2. Gas chromatography-ion mobility spectrometry (GC-IMS) analysis:

[0043] Weigh 2.0 g of the lotus root powder samples of Example 1 and Comparative Examples 1-2, respectively, put them into a 20.0 mL headspace bottle, and test them using a GC-IMS instrument;

[0044] The test conditions are as follows: incubation temperature 90°C, incubation time 10 min, injection method headspace injection, heating method oscillation heating, injection needle temperature 85°C.

[0045] GC-IMS conditions: carrier gas was high purity N 2 , carrier gas flow rate: initial flow rate 2.0mL / min, maintain for 2min, linearly increase to 10mL / min within 8min, linearly increase to 100mL / min within 10min, linearly increase to 150mL / min within 5min, maintain for 2min; total running time 27min; drift tube temperature 45℃, drift gas is high purity N2, drift gas flow rate 150mL / min, column temperature 60℃.

[0046] Specific results such as Figure 2 As shown: 46, 86 and 93 compounds were identified in Comparative Examples 1 and 2 and Example 1, respectively, indicating that the lotus root powder prepared by hot air drying combined with baking has more flavor substances than that prepared by freeze drying. In particular, the addition of lysine before baking significantly increases the content of flavor substances in the lotus root powder, such as (Z)-6-nonen-1-ol, n-heptanol, linalool oxide, isovalerate isobutyl ester, 1-octen-3-one dimer, L-carvone, 1-octen-3-one polymer, etc. In the hot air drying combined with baking drying process, the addition of lysine before baking helps to form more flavor substances in the lotus root powder.

[0047] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for improving the flavor of lotus root powder, characterized in that: The method comprises the following steps: (1) Raw material cleaning: wash the fresh lotus root, remove the nodes, peel it, and evenly slice it; (2) placing the lotus root slices on a clean gauze, and evenly spreading them in an oven for hot air drying to obtain hot air dried lotus root slices; (3) spraying the lysine solution evenly on the surface of the dried lotus root slices; (4) transferring the lotus root slices sprayed in step (3) into an oven for baking, and obtaining the baked lotus root slices for later use; (5) Grinding and sieving the roasted lotus root slices to obtain lotus root whole powder.

2. The method according to claim 1, characterized in that: The thickness of the slices in step (1) is 3-5 mm.

3. The method according to claim 1, characterized in that: The hot air drying temperature in step (2) is 60-80° C. and the drying time is 2-4 hours.

4. The method according to claim 1, characterized in that: The concentration of the lysine solution in step (3) is 0.25-0.35 g / L.

5. The method according to claim 1, characterized in that: The baking parameters in step (4) are: upper heat 105-115° C., lower heat 120-130° C., and baking for 8-12 minutes.

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